Activity Guided Isolation of Antioxidant Tannoid Principles from Anogeissus latifolia

Raghavan Govindarajan1*,Madhavan Vijayakumar1,,Annie Shirwaikar2,,Ajay Kumar Singh Rawat1,,Shanta Mehrotra1,,Palpu Pushpangadan1 한국생약학회 2005 Natural Product Sciences Vol.11 No.3

Oxidative stress is an important causative factor in several human chronic diseases, such asatherosclerosis, cardiovascular disorders, mutagenesis, cancer, several neurodegenerative disorders, and the agingprocess. Phenolics and tannins are reported to be good antioxidants. Anogeissus latifolia (Combretaceae) bark hasnot available till date. Hence the present study was undertaken to isolate antioxidant compounds by activity-guided isolation. Inhibtion of diphenyl picryl hydrazyl (DPH) and Xanthine oxidase along with photoc-hemiluminescence assay were used as bioassay for antioxidant activity. Activity guided isolation was carried outusing silica column and the compounds were quantified using HPLC. Ethyl acetate and butanol fraction exhibitedpotent antioxidant activity. Bioassay-guided isolation led to isolation of ellagic acid (1) and dimethyl ellagic acid(2these three major tannoid principles present in A. latifolia, are responsible for the antioxidant potential andpossibly their therapeutic potential.

In vitro Antioxidant Activity of Ethanolic Extract of Chlorophytum borivilianum

R. Govindarajan1,,N. Sreevidya1,,M. Vijayakumar1,,M. Thakur2,,V.K. Dixit2,,S. Mehrotra*1,,P. Pushpangadan1 한국생약학회 2005 Natural Product Sciences Vol.11 No.3

Chlorophytum borivilianum Baker (Antharicaceae) comonly referred as ‘Safed Musli’ has beenwidely used in the Indian traditional systems of medicine to treat various diseases like rheumatism apart fromaphordisiac properties. C. borivilianum was screened for the first time to determine its antioxidant activity,isolation of the sapogenins and standardization of the isolated sapogenin fraction using HPTLC. Potent antioxidantactivity of ethanolic extract was found by their ability to scavenge DPPH (84.51%), hydroxyl radical (48.95 %),feryl bi-pyridyl complex (84.53%) along with the inhibition of lipid peroxidation (67.17%) at 100g/mlconcentration. The ethanolic extract also exhibited significant inhibition of superoxide anion radical generated byplant in the traditional system especially its use as a Rasayana drug.

Cu-Zn-Co oxide nanoflakes on Ni-foam as a binder free electrode for energy storage applications

Vijayakumar, Subbukalai,Lee, Seong-Hun,Nagamuthu, Sadayappan,Ryu, Kwang-Sun Elsevier 2018 Materials letters Vol.219 No.-

<P><B>Abstract</B></P> <P>Cu-Zn-Co oxide nanoflakes were grown on Ni-foam using a hydrothermal method. FESEM revealed a thin nanoflake-like morphology. The Cu-Zn-Co oxide nanoflakes exhibited a maximum specific capacity of 215 C g<SUP>−1</SUP> at a scan rate of 5 mV s<SUP>−1</SUP> and 178 C g<SUP>−1</SUP> at a specific current of 1 A g<SUP>−1</SUP>. When used as a Li-ion battery electrode, the Cu-Zn-Co oxide nanoflakes exhibited a specific discharge capacity of 1117 mA h g<SUP>−1</SUP> in the second cycle with excellent cycling stability. This superior cycling stability of the Cu-Zn-Co oxide nanoflakes was attributed to the direct attachment of Cu-Zn-Co oxide nanoflakes on Ni-foam.</P> <P><B>Highlights</B></P> <P> <UL> <LI> The Cu-Zn-Co oxide grown on Ni-foam shows thin nanoflake like morphology. </LI> <LI> Cu-Zn-Co oxide nanoflakes exhibits a maximum specific capacity of 215 C g<SUP>−1</SUP>. </LI> <LI> Cu-Zn-Co oxide nanoflakes exhibits a specific discharge capacity of 1603 mA h g<SUP>−1</SUP>. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

Intractable anal pain in B-cell acute lymphocytic leukemia patients: treatment options

Vijayakumar, Vissnukumar,Agarwal, Anil,Shamshery, Chetna,Gautam, Sujeet The Korean Pain Society 2019 The Korean Journal of Pain Vol.32 No.1

Development of Tungsten Trioxide Using Pulse and Continuous Electrodeposition and Its Properties in Electrochromic Devices

Vijayakumar, Elayappan,Yun, Yong-Han,Quy, Vu Hong Vinh,Lee, Young-Hoon,Kang, Soon-Hyung,Ahn, Kwang-Soon,Lee, Seung Woo Electrochemical Society 2019 Journal of the Electrochemical Society Vol.166 No.4

<P>To develop an economical, efficient, and highly stable electrode having high transmittance modulation, thin films of tungsten trioxide (WO<SUB>3</SUB>) were deposited on an Indium-doped tin oxide (ITO) glass substrate by using simple one-step pulse voltage electrodeposition (PVE) and continuous voltage electrodeposition (CVE) routes. Electrochemical and optical analyses demonstrated that the WO<SUB>3</SUB> electrode prepared by PVE possessed high switching speed, high coloration efficiency, and excellent cyclic stability. Moreover, its stable performance in the colored state extended for a long duration even after the voltage was cutoff. The coloration efficiency values were determined to be 69.00 and 43.00 cm<SUP>2</SUP>/C for W-PVE-600s and W-CVE-200s, respectively. The excellent electrochemical and electrochromic properties were mainly attributed to large surface area of W-PVE-600s, which facilitated charge transfer and promoted insertion/exertion of H<SUP>+</SUP> ions in electrolytes better than the WO<SUB>3</SUB> electrode prepared by conventional methods. The significant electrocatalytic activity and stable performance have proved that the proposed W-PVE-600s film can be an alternative to conventional electrodes used in smart window technology applications.</P>

Porous thin layered nanosheets assembled ZnCo₂O₄ grown on Ni-foam as an efficient electrode material for hybrid supercapacitor applications

Vijayakumar, Subbukalai,Nagamuthu, Sadayappan,Lee, Seong-Hun,Ryu, Kwang-Sun Pergamon Press 2017 International journal of hydrogen energy Vol.42 No.5

<P><B>Abstract</B></P> <P>Thin layered nanosheets of ZnCo<SUB>2</SUB>O<SUB>4</SUB> with desirable porous nanoarchitecture grown on Ni-foam were prepared using a simple surfactant free hydrothermal method. The Ni-foam supported ZnCo<SUB>2</SUB>O<SUB>4</SUB> nanostructure was characterized using X-ray diffraction (XRD) analysis, field emission scanning electron microscopy (FESEM), and transmission electron microscopy (TEM). FESEM clearly revealed thin nanosheets which were randomly connected together to form a porous structure. The binder-free Ni-foam supported ZnCo<SUB>2</SUB>O<SUB>4</SUB> electrode was applied directly to hybrid supercapacitor analysis. In three electrode measurement, thin layered nanosheets of ZnCo<SUB>2</SUB>O<SUB>4</SUB> exhibited a maximum specific capacity of 886 C g<SUP>−1</SUP> at a current density of 2 mA cm<SUP>−2</SUP>. When the current density was increased from 2 to 50 mA cm<SUP>−2</SUP>, the specific capacity value was 362.5 C g<SUP>−1</SUP>. After 2000 continuous charge–discharge cycles, about 94% of the maximum specific capacity was retained. This high specific capacity, better rate capacity, and excellent cyclic stability of thin layered nanosheets of ZnCo<SUB>2</SUB>O<SUB>4</SUB> suggest that the prepared electrode is a promising candidate for hybrid supercapacitor applications.</P> <P><B>Highlights</B></P> <P> <UL> <LI> This paper reports the hydrothermal preparation of ZnCo<SUB>2</SUB>O<SUB>4</SUB> on Ni-foam. </LI> <LI> The ZnCo<SUB>2</SUB>O<SUB>4</SUB> nanosheet exhibits maximum specific capacity of 886 C g<SUP>−1</SUP>. </LI> <LI> After 2000 cycles, 103% of the initial specific capacity was retained. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>Binder-free, Ni-foam supported thin layered nanosheets of ZnCo<SUB>2</SUB>O<SUB>4</SUB> were successfully fabricated via a surfactant-free hydrothermal method. This desirable thin layered nanosheets of ZnCo<SUB>2</SUB>O<SUB>4</SUB> nanoarchitecture grown on Ni-foam exhibited the high specific capacity of 886 C g<SUP>−1</SUP> at 2 mA cm<SUP>−2</SUP> with excellent cyclic stability (103%) for 2000 charge–discharge cycles.</P> <P>[DISPLAY OMISSION]</P>

<i>In-vitro</i> assessment of the probiotic potential of <i>Lactobacillus plantarum</i> KCC-24 isolated from Italian rye-grass (<i>Lolium multiflorum</i>) forage

Vijayakumar, Mayakrishnan,Ilavenil, Soundharrajan,Kim, Da Hye,Arasu, Mariadhas Valan,Priya, Kannappan,Choi, Ki Choon Elsevier 2015 Anaerobe Vol.32 No.-

<P><B>Abstract</B></P> <P>The aim of the present study was to determine the probiotic potential of the lactic acid bacteria <I>Lactobacillus plantarum</I> KCC-24 (<I>L. plantarum</I> KCC-24), that was isolated and characterized from Italian ryegrass (<I>Lolium multiflorum</I>) forage. The following experiments were performed to assess the probiotic characteristics such as antifungal activity, antibiotic susceptibility, resistance to low pH, stimulated gastric juice and bile salts, proteolytic activity, auto-aggregation, cell surface hydrophobicity, and <I>in vitro</I> antioxidant property. The isolated <I>L. plantarum</I> KCC-24 exhibited significant antifungal activity against the various fungal strains of <I>Aspergillus fumigatus</I> (73.43%), <I>Penicillium chrysogenum</I> (59.04%), <I>Penicillium roqueforti</I> (56.67%), <I>Botrytis elliptica</I> (40.23%), <I>Fusarium oxysporum</I> (52.47%) and it was susceptible to numerous antibiotics, survived in low pH, was resistant to stimulated gastric juices and bile salts (0.3% w/v). Moreover, <I>L. plantarum</I> KCC-24 exhibited good proteolytic activity. In addition <I>L. plantarum</I> KCC-24 showed potent antioxidant and hydrogen peroxide resistant property. In conclusion, the isolated <I>L. plantarum</I> KCC-24 exhibited several characteristics to prove it's excellent as a potential probiotic candidate for developing quality food for ruminant animals and human.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Lactic acid bacteria have been used in food industries for food preservation. </LI> <LI> Potential probiotic of LAB isolated from Italian Rye-grass forage. </LI> <LI> KCC-24 revealed good antifungal activity against various fungal genera. </LI> <LI> Isolated lactic acid bacteria KCC-24 showed significant probiotic properties. </LI> <LI> <I>L. plantarum</I> KCC-24 showed the good free radical scavenging activity. </LI> </UL> </P>

Enhancement of Nutritional Quality of Italian Ryegrass Mediated Silage by Supplemented with Lactic Acid Bacteria and Chlorella

Vijayakumar, Mayakrishnan,Ilavenil, Soundarrajan,Arasu, Mariadhas Valan,Jung, Min-Woong,Park, Hyung Soo,Kim, Ji Hea,Lim, Young Cheol,Choi, Ki Choon The Korean Society of Grassland and Forage Science 2014 한국초지조사료학회지 Vol.34 No.3

The aim of present study was to improve the quality of silage using lactic acid bacteria (LAB) and chlorella as a supplement. Italian ryegrass (IRG) mediated silage was prepared with lactic acid bacteria (L. plantarum) and different concentration of chlorella. We analyzed the nutritional profiles such as crude protein (CP), acid detergent fiber (ADF) neutral detergent fiber (NDF), total digestible nutrient (TDN) and in-vitro dry matter digestibility (IVDMD), microbial counts and fermentative acids such as lactic acid, acetic acid and butyric acid in the control and experimental silage after three months. It shows increased crude protein content and also maintains the rest of nutritional values as compared with control silage. LAB inoculation with chlorella as supplementation slightly reduced the pH of the silage. In addition, it increased the fermentative acids production as compared with control silage and inhibits the undesired microbial growth especially fungi in the silage. Therefore, we suggest that LAB inoculation and chlorella supplementation to the IRG mediated silage could be improved the nutritional quality of the silage which is an intrinsic feature for the application in the preparation of animal feeds and functional foods.

A Palm Vein Recognition System based on a Support Vector Machine

Vijayakumar Ponnusamy,Abhijit Sridhar,Arun Baalaaji,M. Sangeetha 대한전자공학회 2019 IEIE Transactions on Smart Processing & Computing Vol.8 No.1

Palm vein authentication is among the recent research in the field of access control applications. Because palm veins are tough to forge, they act as a reliable metric in security applications. Accurate extraction of palm veins is challenging in the presence of various dynamics, such as variant light conditions, variations in palm vein patterns from person to person, the cleanliness of the hand, etc. This paper presents a robust recognition process that makes use of a ridge filter for vein pattern extraction, and local binary patterns (LBP) for feature extraction. The ridge filter takes the major eigenvalue of the Hessian matrix, which contains the second-order derivative of the image pixels. The eigenvalue is then processed using LBP feature extraction from the vein patterns. Finally, a support vector machine is used for classification of subsequent images. The result shows that the system can provide accuracy of 89%, with a computation time of 0.423s. The false acceptance rate and false rejection rate were also evaluated as benchmark parameters, which show significantly good performance.

Recent Advances in Polybenzimidazole (PBI)-based Polymer Electrolyte Membranes for High Temperature Fuel Cell Applications

Vijayakumar, Vijayalekshmi,Kim, Kihyun,Nam, Sang Yong The Korean Society of Industrial and Engineering C 2019 공업화학 Vol.30 No.6

Polybenzimidazole (PBI), an engineering polymer with well-known excellent thermal, chemical and mechanical stabilities has been recognized as an alternative to high temperature polymer electrolyte membranes (HT-PEMs). This review focuses on recent advances made on the development of PBI-based HT-PEMs for fuel cell applications. PBI-based membranes discussed were prepared by various strategies such as structural modification, cross-linking, blending and organic-inorganic composites. In addition, intriguing properties of the PBI-based membranes as well as their fuel cell performances were highligted.